In some types of communication systems, a transmitter encodes a sequence of data values into a serial data signal based on a transmit clock signal and transmits the serial data signal to a receiver in the communication system. The receiver reconstructs the transmit clock signal based on the serial data signal received from the transmitter and recovers the sequence of data values from the serial data signal based on the reconstructed clock signal.
Generally, the frequency of the reconstructed clock signal is based on the data rate of the serial data signal and is the same as the frequency of the transmit clock signal. In some cases, the receiver may reconstruct the transmit clock signal to have a harmonic frequency of the frequency of the transmit clock signal instead of the frequency of the transmit clock signal. As a result, the receiver does not accurately recover the sequence of data values from the serial data signal.
In light of the above, a need exists for an improved system and method of reconstructing a clock signal from a serial data signal. A further need exists for detecting a harmonic frequency in a clock signal reconstructed from a serial data signal.